Heating furnace



Nov. 22, 1938.

&51

E. LUNDT 2,137,693

HEATING FURNACE I Filed Feb. 11, 1938 4 Sheets-Sheet 1 a 55 BID {0 12 gk as 59 8 kts.

WITNESSES INVENTOR frames? 0 L 1471,6117

Ma-LMMW ATTORNEYS Nov. 22, 1938. E. C. LUNDT HEATING FURNACE Filed Feb.11, 1938 4 Sheets-Sheet 2 INVENTOR I ErneefC.Lun'cZZ WITNESSESA'ITORNEYS Nov. 22, 1938. E. c. LUNDT HEATING FURNACE Filed Feb. 11,1958 4 Sheets-Sheet 5 INVENTOR Ernesi'C Lundt BY M Ma- W ATTORNEYS WINESSES Nov. 22, 1938. Q LUNDT 2,137,693

HEATING FURNACE Filed Feb. 11, 1938 4 Sheets-Sheet 4 wnwzsscs U INVENTORZ'rnest C. L and? ATTORN EYS Patented Nov. 22, 1938 UNITED STATESHEATING FURNACE Ernest o. Lundt, Bloomfield, N. 1., winner, by memoassignments, to American Radiator Company, New York, N. Y., acorporation of New Jersey Application February 11, 1938, Serial No.189,929

8 Claims.

This invention relates to heating furnaces, and particularly to animproved gas heated furnace which may be used for melting metal or otherdesired material, the object being to provide a construction which willutilize substantially all of the heat created.

Another object of the invention is to provide a heating furnace whereinthe heating members are arranged within a pot and the exhaust from theheating members is used to heat the side and bottom of the pot.

A further object of the invention is to provide a heating furnacewherein means are presented for applying a preponderance of the heat tocertain specified zones both within and without a pot forming part ofthe furnace.

In the accompanying drawings:

Fig. 1 is a sectional view through Fig. 4 approximately on the line l-l;

Fig. 2 is a sectional view through a suction device embodying certainfeatures of the invention;

Fig; 3 is a sectional view through an inspirator and associated devicespresenting certain features of the invention;

Fig. 4 is a top plan View of a complete heating furnace embodying theinvention;

Fig. 5 is a sectional view through Fig. 4 approximately on the line 55,the same being on a slightly reduced scale;

Fig. 6 is a top plan view of the container or pot shown in Fig. 5;

Fig. 7 is a side view of the pot shown in Fig. 6;

Fig. 8 is a view similar to Fig. 7 but showing the opposite side of thepot.

Referring to the accompanying drawings by numerals, i indicates a potand 2 a casing which is preferably provided with a metal lining 3 andsuitable heat insulating material 4 so as to hold or retain the heatagainst radiation. The pot i is provided with a radiating flange 5 whichpreferably rests on casing 2 and which may be secured to the casing ifdesired. The pot l is shown in detail in Figs. 6, 7 and 8. From thesefigures it will beseen that the pot l is provided with a body 6 havingthe flange 5 integrally formed therewith and also a number of side websI and bottom webs 3. The side webs l are arranged vertically when thedevice is in use and the horizontal webs 8 are arranged in a horizontalposition on the bottom of the pot. It will also be noted that the bottomedges of all of the webs are in the same horizontal plane so that theyall may rest on the bottom section of lining3 while the flange 5 restson the upper edge of easing 2. It will be noted that the webs l are ofdiilerent heights so as to provide a tortuous passageway which coactswith the tortuous passageway provided by the various webs 8 on thebottom. As shown in the accompanying drawings there have been providedfour independent tortuous passageways, but ii desired the device couldbe made with two or even one without departing from the spirit of theinvention.

As shown in Fig. 1 the various heating pipes 9 are arranged so thattheir discharge ends will discharge into the various passageways II!which in turn discharge into the inlets of the various tortuouspassageways ll. These pipes as shown in Fig. 5 extend to a point abovethe flange 5 so that they may be readily removed after the clamps orsupporting saddle 38 and the retaining bolts 9' (Fig. 4) have beenremoved. It will be understood that the outlet end of each of the pipes9 discharges into an independent passageway l and consequently into anindependent tortuous passageway II. From Fig. 1 it will be noted thatthere is a lining i2 for the passageway I II which is protected by anouter shield I3 so that the products of combustion from the respectivepipes 9 will lose little or none of their heat units before theydischarge into the desired tortuous passageway. As indicated in Fig.there are four tortuous passagewaysjnamely. passageways I, I5, i6 andi1. These passageways lead from the various inlet openings H, l5, l6 andIT to the various outlet openings l3, I9, 29 and 2 l. The openings I 8and I9 discharge into the outlet or exhaust pipe 22 and the openings 29and 2| discharge into the outlet or exhaust pipe 23. Associated witheach of the outlets 22 and 23 is a damper 24 which may be of any desiredkind and which may be operated from an outside lever 25 so as to varythe inlet part of the members 22 and 23. It will therefore be seenparticularly from Fig. 1 of the drawings that the exhaust enters thetortuous passageways on one side of the pot and leaves the tortuouspassageways on the opposite side.

A suction device 2! is connected with each of the exhaust pipes 22 and23 so as to provide suction to relieve or eliminate back pressure in thevarious tortuous passageways as well as in the pipes 3. This suctiondevice may be of any desired kind, but as shown it consists of adischarge nozzle 2'! merging into a casing 28 forming a suction chamber29. An air nozzle 30 is arranged\ in chamber 29 and is supplied with airunder pressure from any suitable source whereby as the air is dischargedinto the nozzle 2'! rarefaction will be produced inchamber 29 and thegravity closed flap valve 3| will be opened. If there is no combustiblemixture being fed into the pipes 9 the action of the suction device willdraw air into the pipes 9 and also into the various tortuous passagewaysso as to clean them of previous products of combustion. However,ordinarily the inspirator 32 is used for directing a combustible mixtureinto each of the pipe: 9. It will be understood that there is aninspiratcr 32 for each pipe and that the various inspirators direct thecombustible mixture into the inlet end of the pipes 3. The inspiratorsupplies a mixture of air and gas and as this air and gas is supplied inpipe 3 it will draw in secondary air through the shutter 33 whereby aproper mixture is provided for the heating pipes 9 which really formwhat are known as closed combustion chambers, although they are open atboth ends.

As shown in Fig. 4 the various pipes 3 are arranged into what may becalled groups 34 and 35. These groups 34 and 35 are arranged immediatelyabove the respective zones or areas 38 and 31 of the pot i. All of thepassageways act to permit heat to be applied to the areas 38 and 31exteriorly of the bottom of the pot or container l. The groups 34 and 35also apply heat to zones or areas immediately above the zones or areas38 and 31. From Figs. 1 and 5 it will be observed that all of the pipes9 are spaced from the pot I and that the larger parts of the variouspipes form groups 34 and 35 arranged in a horizontal plane a shortdistance above the bottom of the pot or container I. In order to preventany rising movement of the pipes 3 when the device is in use, there isprovided a retaining bracket 33 for each group of pipes. These retainingbrackets are secured by screws or other wise to flange 5 and by suitableclips 33 to the respective pipes.

It will be seen that each pipe receives an ignited supply of combustiblemixture at its inlet end when the device is in use and combustion takesplace within the respective pipes so that the products of combustionwhile hot will be discharged out through passageway Ill into one .of thetortuous passageways. The various tortuous passageways are arranged asshown in Figs. 4 and 6 so that all parts of the side walls and bottom ofthe pot will be heated and zones 33 and 31 will receive more heat unitsthan any one part. This arrangement with the position of the groups 34and 35 presents adjacent hot zones which will maintain the metal orother substance fully heated. Also by heating all parts of the pot thetemperature throughout the material carried. by the pot will beapproximately the same.

I claim:

1. A heating furnace comprising a container having a plurality -ofspaced webs on the outer surface of the side walls and the bottom, acasing for said container coacting with said webs for forming aplurality of tortuous passageways, a plurality of heating pipespositioned in said container and located so that the outlet end willdischarge into the inlet end of said tortuous passageways, means fordirecting an ignited combustible mixture into the inlet end of saidheating pipes, and means at the outlet end of said tortuous passagewaysfor producing a suction.

2. A heating furnace comprising a metallic container having a pluralityof spaced webs integral with the container and positioned to extendoutwardly from the outer surface of the sides and bottom of thecontainer, means coacting with said webs for forming a tortuouspassageway, a heating pipe positioned in said container and spaced fromthe walls thereof, said pipe being arranged so that the outlet endthereof will discharge into the inlet end of said tortuous passageway,means for discharging a combustible mixture into the inlet end of saidpipe, and means for producing a suction in the outlet end of saidtortuous passageway.

3. A heating furnace comprising a pot having webs on its outer surface,a heat insulating casing surrounding said pot and coacting with the websand body of the pot to form a plurality of tortuous passageways, aheating pipe with the" principal part located within said pot for eachof said passageways, each of said pipes having the outlet end connectedto the inlet end of one of said tortuous passageways, means at the inletend of each of said pipes for discharging a combustible mixture therein,and suction means at the outlet end of each of said tortuous passagewaysfor removing back pressure to the incoming combustible mixture.

4. A heating furnace comprising a cast metal pot formed with a bodyhaving an integral radiating flange at the top, vertically arrangedspaced webs on the sides and horizontally extending webs on the bottom,a casing coacting with said body and all of said webs for forming aplurality of tortuous passageways, a heating pipe for each of saidpassageways, said heating pipes at their discharge ends discharging intothe inlet ends of said tortuous passageways, means at the inlet ends ofsaid pipes for discharging a combustible mixture into said pipes, andsuction means at the outlet end of each of said tortuous passagewaysacting to remove back pressure in said pipes. 5. In a heating furnace apot having a body formed with a radiating flange at the top, a pluralityof spaced vertically positioned webs on the sides and a plurality ofhorizontally positioned webs on the bottom, the bottom of saidhorizontal webs and said side webs being in a horizontal plane.

6. A heating furnace including a pot having a plurality of upstandingwebs on the sides and bottom, and a casing enclosing the sides andbottom of said pot acting in conjunction with the body and webs of thepot to present tortuous hot gas carrying passageways grouped to apply apreponderance of heat units to adjacent areas of the bottom of said pot,and removable heating pipes arranged within said pot whereby the pot isheated from without by one heating element and heated from within by adifferent heating element.

'7. A heating furnace comprising, a pot formed on its outer surface withspaced vertical webs on the sides and spaced horizontal webs on thebottom, a casing covering the sides and bottom of said pot includingsaid webs, said casing and pot with its webs forming tortuous hot gascarrying passageways grouped to apply a preponderance of heat units toadjacent zones of the bottom of said pot, a plurality of groups ofheating pipes positioned in said pot, said groups of heating pipes beingpositioned to apply a preponderance of heat units to areas immediatelyabove said zones, and means for directing a heating medium into saidpipes.

8. A heating furnace comprising a pot, a series of heating pipes using acombustible mixture, said pipes being arranged within said pot butspaced therefrom, and means utilizing the exhaust from said pipes forheating from the outside the bottom and side walls of said pot.

ERNEST c. p m.

